I imported a step file of a part from a vendor. It imported fine, but I can not edit the custom properties at all. I can not delete the existing custom properties and I can't add new ones. ll the lines in the custom properties box are greyed out. I have never seen this with other imported files before. I am running SW 2018 SP2
On a regular part the first 3 columns are not greyed out
Could you attach your file?
Maybe 3D interconnect is On...try to switch off
2017 SOLIDWORKS Help - SOLIDWORKS 3D Interconnect